Lignin, which represents 15-35% of wood, is the most abundant renewable organic material on the earth. The pulping industry separates cellulose from the wood composition resulting in lignin and hemicellulose waste by-products known as black liquor and spent pulp liquor. In the sulphite process, the main by-product contained in the spent pulp liquor is lignosulphonate. With each ton of pulping products producing 330-540 Kg of lignosulphonate, the global annual production capacity of lignosulphonate is about 1.8-2.0 million tons. Most of the lignosulphonate (66%) produced in pulping industries is burned as fuel and 34% is treated and disposed. Using this waste stream as a fuel source is inefficient, and releases large amounts of pollutants such as SO2. Simple disposing of lignin, on the other hand, incurs a significant cost to the pulping industry.
Surfactants have myriad industrial and consumer uses. The world production of surfactants in 1990 was 40 million tons which increased to 60 million tons by 2010. Surfactants are used in soaps, detergents, dispersants for dyestuffs, admixtures for concrete as water reducers and plasticizers, emulsifiers for bitumen and agrochemicals such as pesticides and fungicides. They are also used in enhanced oil recovery and oil drilling, wetting agents for textiles and pharmaceuticals, foaming agents, and demulsifying agents. Lignin-based surfactants could replace the current industrial manufacture of surfactants, particularly those based on petrochemical resources, which use non-renewable resources, are expensive, and create non-biodegradable surfactants.